import re

html = '''
<div class="tail-info">客户端</div>
<div class="tail-info">2023-12-12 15:30:56</div>
'''

result_1 = re.findall('tail-info">(.*?)<', html)
result_2 = re.findall('tail-info">2023(.*?)<', html)
result_3 = re.findall('tail-info">(202.*?)<', html)

print('括号里只有.*?时，得到的结果：{}'.format(result_1))
print('2023在括号外时，得到的结果：{}'.format(result_2))
print('2023在括号里面时，得到的结果：{}'.format(result_3))



